The gasification furnace of the present disclosure refers to a coal gasification furnace, also known as a gas producer, which is a furnace for producing the combustible gas by using a coal as a gasification fuel. The waste boiler (i.e., waste heat boiler, also known as exhaust heat boiler (waste heat boiler)) is a heat exchanger for producing the steam by using the high-temperature logistics in the production process as a heat source, which is both a cooler of high-temperature substance stream in the process and a power device which is provided steam by means of the waste heat.
The gasification furnace in the related art, such as a gasification furnace with a waste boiler having a radiation waste boiler assembly, has been widely recognized in the gasification field. The characteristics which the above gasification furnace can burn cheap coal having a high ash melting point make a number of user manufacturers to obtain a remarkable profit, and radiant heat of high temperature crude coal gas has been recovered in the form of steam, and then crude coal gas has quenched to the required temperature by means of water. The traditional gasification furnace with a waste boiler needs to adjust the flow rate of the ash-discharging water to control the liquid level of the quenching chamber to ensure that the water film passage is in a safe position below the liquid level, but it can't be foolproof to control the liquid level by the man-made operation and the instrument, and there is a certain security risk.
The Chinese patent document, entitled Publication No. CN202881213U, discloses a liquid level holding device of a gasification furnace quenching chamber for a water quenching process comprising a gasification furnace main body, a scrubber (washing tower), a high pressure condensate tank and a condensate pump; wherein the product gas outlet pipe of the gasification furnace main body is communicated with the scrubber, and the high pressure condensate tank is respectively communicated with the gasification furnace main body, the product gas outlet pipe and the scrubber through the condensate pump, and further comprising a condensate water supply pipe which is communicated with the condensate inlet pipe provided on the product gas outlet pipe of the gasification furnace main body, and a connection loose joint is provided at the top of the medium pressure nitrogen inlet pipe of the gasification furnace main body. The medium pressure nitrogen inlet pipe and the condensate water supply pipe are movably connected by the connection loose joint. The condensate water supply pipe and the medium pressure nitrogen inlet pipe are provided with cut-off valves, respectively. It has advantages of improving the operating cycle of the gasification furnace, reducing the number of turning down the gasification furnace, and decreasing the economic loss and the security risk.
The Chinese patent document, which has Application Publication No. CN104101402A, discloses an accurate measurement system for the liquid level of a gasification furnace quenching chamber, comprising a gasification furnace quenching chamber and a differential pressure level gauge. The lower part of said gasification furnace quenching chamber is provided with a double flange differential pressure level transmitter connected with the density operation module through the signal line, and the density operation module is connected with the differential pressure level gauge through the signal line. The upper flange mouth and the lower flange mouth of the double flange differential pressure level transmitter are respectively arranged in the lower part of the gasification furnace quenching chamber, and the position connected the upper flange mouth to the gasification furnace quenching chamber is between the minimum running level and the level of an oven. The accurate measuring system of the disclosure can not only measure the actual height of the liquid level in real time, but also ensure the measurement of the liquid level in the oven.
The above method and apparatus for maintaining the liquid level of the gasification furnace are both complex and costly and still require manual operation. Therefore, there is a need in the art for a gasification furnace product which is simple in construction, easy in installation and maintenance, and does not require manual operation and which can fundamentally ensure the safety of the liquid level of the gasification furnace. In addition, from the viewpoint of energy saving and energy comprehensive utilization, the gasification furnace should also be equipped with a waste boiler assembly.